Sensitive Freezer Alarm with Buzzer

Published:2012/9/24 4:20:00 Author:muriel | Keyword: Sensitive， Freezer Alarm | From:SeekIC

Here is a simple freezer alarm circuit, but ultra sensitive with a buzzer. The circuit raises an audio alert when the temperature inside the freezer box goes up above a preset level. The circuit requires 9V dc supply and can power from a standard 9V alkaline battery.A negative temperature co-efficient type (NTC type) small thermistor (R1) here works as the freezer status sensor. Related components (T1 and T2) are used to drive a 6 to 9V rated mechanical buzzer. When the sensor detects a temperature shoot, the buzzer starts beeping and remains in that condition, till power to the circuit is removed. For this on/off plus reset function any small dc toggle switch can be inserted at the positive rail. Freezer Alarm Circuit Schematic ? 2 Responses to “Sensitive Freezer Alarm with Buzzer”



Reprinted Url Of This Article:
http://www.seekic.com/circuit_diagram/Signal_Processing/Sensitive_Freezer_Alarm_with_Buzzer.html

Print this Page | Comments | Reading(3)